Traversing printer

ABSTRACT

A method and apparatus for spraying a predetermined pattern of liquid onto each of a plurality of articles carried by a continuously moving conveyor. As the articles respectively move through a spraying station adjacent the conveyor an apertured mask is moved into frictional engagement with each article and is moved by the article in unison therewith for a short distance while a spray of said liquid is directed by the gun through the mask onto the article.

United States Patent Warning et al.

[ 1 TRAVERSING PRINTER [75] Inventors: Walter B. Warning, Chicago;

Walter B. Warning, Jr., Schaumberg, both of I11.

[73] Assignee: Automation Development and Engineering Corporation, Elk Grove Village, Ill.

[22] Filed: Apr. 22, 1974 [21] Appl. No.: 462,617

[52] US. Cl. 118/2; 118/301; 118/323; 118/324; 101/124 [51] Int. Cl. B05C 11/00; BOSC 5/00; 8053 15/04 [58] Field of Search 118/301, 323, 504, 324, 118/505, 2, 8', 101/124; 68/205 R [56] References Cited UNITED STATES PATENTS 1,807,979 6/1931 Groetschel 101/124 NOV. 18, 1975 3,143,960 8/1964 Naczynski 118/301 X 3,252,411 5/1966 Black 101/124 3,292,532 12/1966 Berk 6t :11. 118/301 X Primary Examiner-John P. McIntosh Attorney, Agent, or FirnzEdmond T. Patnaude [57] ABSTRACT A method and apparatus for spraying a predetermined pattern of liquid onto each of a plurality of articles carried by a continuously moving conveyor. As the articles respectively move through a spraying station adjacent the conveyor an apertured mask is moved into frictional engagement with each article and is moved by the article in unison therewith for a short distance while a spray of said liquid is directed by the gun through the mask onto the article.

2 Claims, 6 Drawing Figures U.S. Patent Nov. 18, 1975 SheetlofZ 3,919,967

U.S. Patent Nov. 18, 1975 Sheet20f2 3,919,967

TIME DELAY OFF TIME DELAY ON INITIATING SIGNAL FIG. 3

TIME

* DELAY TRAVERSING PRINTER The present invention relates in general to the art of spraying a predetermined liquid pattern onto continuously moving articles, and it relates more particularly to a new and improved method and apparatus suitable for printing visually readable matter on rapidly moving articles such, for example, as containers.

BACKGROUND OF THE INVENTION While the system and method of this invention find application in other fields, the invention is particularly suited for applying visible information on cartons or other packages carried by a continuously moving conveyor. The apparatus is used to apply code dates and other data to packages of food, irregularly shaped bags of granular material and the like and it is also used to print relatively large alpha-numeric characters such as company names and addresses on cartons and the like. As will be apparent to those skilled in the art features of the invention may be used for spraying a predetermined pattern of most any liquid, visible and in some cases invisible, on continuously moving articles as they pass through a spray station along the route of the conveyor.

SUMMARY OF THE INVENTION Briefly, there is provided in accordance with the present invention a system wherein an apertured mask engages and is moved by the articles carried by a conveyor through the spraying station as an atomized liquid spray is directed through the mask onto the articles. In one embodiment of the invention, the spray means and the mask move in unison with the article through the spray station and in another embodiment the spray means is stationary and the mask and article being sprayed move in unison past the gun. The first embodiment is primarily used for marking small indicia such as code dates and the like wherein the spray pattern is sufficiently large to encompass the entire apertured portion of the mask while the second embodiment is generally used for printing larger areas where the required spray pattern would otherwise be excessively large.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understand from the following detailed description taken in connection with the accompanying drawings wherein:

FIG. 1 is an elevational view of a marking system embodying the present invention;

FIG. 2 is an elevational view of another marking system embodying the present invention;

FIG. 3 is a schematic diagram of the control system which operates the apparatus of FIG. 1;

FIG. 4 is a view of the apparatus of FIG. 1 taken from the line 4-4 thereof;

FIG. 5 is a partially sectioned view of the apparatus of FIG. 4 taken along the line 55 thereof; and

FIG. 6 is a sectional view of the mask holder of FIG. 4 taken along the line 6-6 thereof.

DETAILED DESCRIPTION OF THE INVENTION With reference to FIGS. 1, 4 and 5 of the drawings, a marking apparatus 10 includes a base plate 11 suitably mounted, for example, by means of a pair of brackets 12 adjacent a conveyor 13 carrying a plurality of spaced apart articles 14 to be marked. As the articles 14 are carried seriatim through the spray station past the apparatus 10, an atomized liquid is sprayed in a predetermined pattern onto the top surfaces of the articles 14. It will be understood by those skilled in the art, however, that the apparatus 10 may also be mounted to either or both of the front or rear sides of the conveyor 13 as shown in FIG. 1 so as to spray said liquid pattern on the sides rather than the tops of the articles.

A pair of support blocks 17 and 18 are secured to the base plate 11 and support a pair of guide rods 19 and 20 in spaced parallel relationship therebetween. As shown, the rods 19 and 20 lie parallel to the conveyor 13 and thus parallel to the path traversed by the articles as they move through the spraying station. A carriage 22 includes a plate 23 from which a pair of bearing blocks 24 and 25 depend. Suitable bearings are carried by the blocks 24 and 25 and slidably receive the rods 19 and 20. A coil spring 26 is supported within a rigid tube 27 which extends from the block 17. One end of the spring is connected by a tension adjustor mechanism 28 to the outer end of the tube 27 and the other end of the spring 26 is connected to the bearing block 24 to resiliently bias the carriage to the leftmost position as illustrated in FIGS. 1 and 4. A pair of cushion stop sleeves 30 are mounted over the rods 19 and 20 between the block 24 and the block 17.

As best shown in FIG. 5, a pair of mounting blocks 32 and 33 fixed to the top of the plate 23 support a pair of guide rods 34 and 35 in spaced parallel relationship therebetween in a direction transverse to the rods 19 and 20. A mask holder assembly 36 includes a bearing block 37 through which the rods 34 and 35 slidably extend whereby the mask holder assembly 36 is movable toward and away from the path of the articles 14 by means of a fluid operated piston and cylinder assembly 38. The cylinder portion of the assembly 38 is fixedly mounted to the mounting block 33 and the piston thereof is attached to the bearing block 37 through a hole in the block 33 intermediate the rods 34 and 35. A support plate 40 is fastened to the bearing block 37 and a set of relatively slidable dove-tailed bars 41 are fastened to the plate 40, and an upright set of similar dove-tailed bars 42 are mounted to the end of the bar 41 adjacent the path of the articles 14. The bars in each set are longitudinally adjustable relative to one another and held in the adjusted positions by means of set screws, not shown. The bar 41 is pivotally mounted by a bolt 43 to the plate 40 and spring loaded to a central position on a post 43a by a pair of springs mounted in a transverse hole in the bar 41. A mask holder assembly 44 is attached to the vertical bar set 42 thereby to be horizontally and vertically adjustable by means of the bar set and the adjustment of the plate 11 on the brackets 12 and 42 respectively. As described in greater detail hereinafter, the assembly 44 supports a mask 46 provided with one or more apertures 47 through which the liquid spray is directed onto the articles 14.

A spray head or gun 50 is mounted to the left hand bracket 12 by means of a vertically disposed dove-tail bar set 51 and a horizontally disposed dove-tail bar set 52 is fastened to one of the bars in the set 51 and to the gun 50 thereby to permit vertical and horizontal adjustment of the spray gun 50. The gun 50 includes a head 53 having one or more orifices in the end directing an atomized liquid spray through the mask 46 onto the adjacent faces of the articles 14 as they move through the spraying station. The gun 50 is operated in response to actuation of a control solenoid valve 54 connected in a pressurized air line to the gun 50. A liquid reservoir,

not shown, is also connected to the gun to feed liquid thereto when the solenoid 54 is energized.

' A solenoid operated four-way valve 56 is mounted to the bracket 12 and connected by flexible conduits 57 and 58 to the front and rear of the cylinder 38 for controllably receiprocating the piston thereof which in turn receiprocates the mask 46 toward and away from the path of the articles. As shown, the valve 56 includes a control solenoid 59 connected thereto.

Referring to FIG. 3, the control circuit schematically shown therein comprises an adjustable time delay mechanism 60 such as a time delay relay providing an output signal at an adjustable predetermined time after an initiating signal is supplied thereto. The initiating signal may come from a switch 61, FIG. 1, which is actuated by an article 14 entering the spraying station or by other means such as a photocell or the like. The output signal from the time delay means 60 passes through a second time delay means 63 which immediately couples the delayed signal from the device 60 to the solenoid 59 of the valve 56 and interrupts such signal after an adjustable time delay period. When the solenoid 59 is energizes it pulls the valve member 64 to align a passageway thereof between an air inlet port 65 and the outlet connecting to the rear end of the cylinder 38 via the-conduit 57 thereby to drive the mask into engagement with the article 14 in the spraying station. A second passageway in the valve member connects the foreward end of the cylinder 38 to the atmosphere through an air outlet orifice whose size is controlled by an adjustment screw controlled bleed valve 67. When the solenoid 59 is deenergized the valve member is returned by spring means (not shown) to its initial position wherein inlet air is supplied to the foreward and of the cylinder 38 and air is exhausted from the rear end through an orifice controlled by an adjustment screw controlled bleed valve 68. The screw operated bleed valves 67 and 68 thus independently control the speeds at which the mask moves toward and away from the article in the spraying station.

The output signal from the time delay means 60 is also supplied to a third time delay means or relay 70 wherein it is delayed for an adjustable predetermined time and coupled through a time delay means or relay 71 to the solenoid 54 which controls the spray gun 50. The signal from the time delay means 70 is immediately coupled by the device 71 to the solenoid 54 and is interrupted at an adjustable predetermined time thereafter whereby the adjustment of the device 70 determines when the spray commences and the adjustment of the device 71 determines the duration of the spray.

The time delay mechanism is adjusted so that the solenoid 59 is actuated at the proper time to move the mask assembly into engagement with the particular portion of the article to be marked. The pivotability of the mask holder on the plate 40 accomodates for any slight misalignment of the articles 14 on the conveyor. The cylinder 38 thus forces and holds the mask assembly against the article to be marked whereby the friction therebetween causes the mask to be carried along in unison with the article, and which causes the carriage assembly to move along the guide rods 19 and 20. The spring 26 is thus stretched as the carriage is moved with the conveyor. As best shown in FIG. 4, the spray head is positioned on the downside of the first portion of the pattern to be sprayed and the time delay device 70 is thus adjustedsuch that the solenoid 54 is energized and the spray commenced shortly before the apertured portion of the mask 46 moves past the head. The time delay means 71 is adjusted so as to de-energize the solenoid and thus terminate the spray shortly after the apertured portion of the mask 46 passes the head. The time delay means 63 is adjusted so as to deenergize the solenoid 59 before the carriage reaches the ends of the rods 19- and 20 whereby to drive the mask assembly out of engagement with the article. As the mask assembly moves back from the article, the carriage assembly is returned to its initial position by the spring 26 whereupon the entire cycle is repeated for the next article 14 on the conveyer 13.

Referring to FIGS. 4 and 6, the mask holder assembly 44 comprises a frame 75 having a rectangular opening 76 over which the mask 46 is mounted with the apertured portion 47 aligned with the opening through the frame. A pair of clamping members 77 and 78 are mounted to a plurality of pins 79 overlying springs 80 which thereby resiliently urge the members 77 and 78 into complimentary recesses in the outer face of the mask frame 75. The mask is a flexible plastic sheet and the ends thereof are inserted between the clamp members 77 and 78 and the adjacent faces of the frame. When a mask 46 is to be mounted in the holder, the clamp members are readily held in the open position by simply pressing the heads of the pins against a support surface while the mask is inserted thereunder.

Referring now to FIG. 2 there is shown a spray marker which is similar to the marker 10 of FIG. 1 but wherein the spray gun 50 is mounted to the support plate 40 thereby to move with the mask holder assembly and the article being marked. The associated control system is the same as that shown in FIG. 3 and like elements in FIG. 2 are identified by the same numerals used in FIG. 1. A mask holder 91 which is much shorter than the mask holder 44 is also pivotally attached to the plate 40. In this marker 90, unlike the marker 10, the spray pattern from the gun exceeds the apertured area of the mask whereby it is unnecessary to cause the spray to sweep across the mask and the underlying surface of the article. In other respects, however, the operation is the same in that the mask is driven and held against the article and is carried thereby through the spraying station while the liquid is sprayed through the mask onto the article, there being no relative movement between the mask and the article while the liquid is being sprayed from the gun 50.

While the present invention has been described in connection with embodiments thereof, it will be understood by those skilled in the art that many changes and modifications may be made without departing from the true spirit and scope of the present invention. Therefore, it is intended by the appended claims to cover all such changes and modifications which come within the true spirit and scope of this invention.

What I claim is:

1. Apparatus for applying a predetermined pattern of liquid onto each of a plurality of articles being transported seriatim by a continuously travelling conveyor, the combination comprising a gun for emitting a spray of said liquid,

means mounting said gun adjacent the path of movement of said articles for spraying said liquid onto said articles,

a mask apertured in the shape of said predetermined pattern,

a carriage mounted for movement in a direction parallel to said conveyor between a first position and a initiating signal for operating said mask moving means to move said mask against said article,

second adjustable time delay means for initiating operation of said gun at a predetermined time after said initiating signal,

third adjustable time delay means for interrupting the operation of said gun after a predetermined time interval of operation, and

fourth adjustable time delay means for then causing said control means to move said mask away from said article.

2. Apparatus according to claim 1 wherein said second time delay means is responsive to a time delayed output signal from said first time delay means. 

1. Apparatus for applying a predetermined pattern of liquid onto each of a plurality of articles being transported seriatim by a continuously travelling conveyor, the combination comprising a gun for emitting a spray of said liquid, means mounting said gun adjacent the path of movement of said articles for spraying said liquid onto said articles, a mask apertured in the shape of said predetermined pattern, a carriage mounted for movement in a direction parallel to said conveyor between a first position and a second position adjacent said path, means mounting said mask to said carriage for movement toward and away from the path of said articles, mask moving means moving said mask into selective engagement with said articles as they move along said path, means moving said carriage between said first and second positions while said mask is in engagement with one of said articles, means responsive to an article being located at a predetermined position on said conveyor for providing an initiating signal, first adjustable time delay means responsive to said initiating signal for operating said mask moving means to move said mask against said article, second adjustable time delay means for initiating operation of said gun at a predetermined time after said initiating signal, third adjustable time delay means for interrupting the operation of said gun after a predetermined time interval of operation, and fourth adjustable time delay means for Then causing said control means to move said mask away from said article.
 2. Apparatus according to claim 1 wherein said second time delay means is responsive to a time delayed output signal from said first time delay means. 